You can convert multi-port network parameters among different formats
(S,Z, Y, H, G,T, ABCD). For example, Y-parameters are convenient for working
with RLC circuits, whereas S-parameters are better for visualizing frequency
responses.

You can also convert single-ended S-parameters to mixed mode S-parameters,
extract M-port S-parameters from N-port S-parameters or change the
characteristic impedance.